ADVENTITIOUS LEAVES—SCALES. 167 
preserves its usual catkin-hke shape, but the flowers 
are replaced by little tufts of leaves. M. Germain de 
Saint Pierre mentions a case wherein the flowers of 
Alisma parnassifolia were completely replaced by leaf- 
buds." 
Here, also, may be mentioned the curious agerega- 
tions of scales which occur in some grasses, in Resti- 
ace, Juncacee, and other orders, in which the inflor- 

Fic. 79.—Spikelets of Fia. 80.—Rose Willow, Salix. sp. 
Willedenovia, composed 
entirely of scales to the \ 
exclusion of flowers. 

* «Bull. Soc. Bot. Fr.,’ 1856, p. 53. 
